Monday, 16 October 1989
Kennedy Space Center, Florida

NASA buzzed with the excitement of a launch. Galileo was finally going to Jupiter.

Administrators and scientists in the world's most prestigious space agency had spent years trying to get the unmanned probe into space. Now, on Tuesday, 17 October, if all went well, the five astronauts in the Atlantis space shuttle would blast off from the Kennedy Space Center at Cape Canaveral, Florida, with Galileo in tow. On the team's fifth orbit, as the shuttle floated 295 kilometres above the Gulf of Mexico, the crew would liberate the three-tonne space probe.

An hour later, as Galileo skated safely away from the shuttle, the probe's 32500 pound booster system would fire up and NASA staff would watch this exquisite piece of human ingenuity embark on a six-year mission to the largest planet in the solar system. Galileo would take a necessarily circuitous route, flying by Venus once and Earth twice in a gravitational slingshot effort to get up enough momentum to reach Jupiter.

NASA's finest minds had wrestled for years with the problem of exactly how to get the probe across the solar system. Solar power was one option. But if Jupiter was a long way from Earth, it was even further from the Sun - 778.3 million kilometres to be exact. Galileo would need ridiculously large solar panels to generate enough power for its instruments at such a distance from the Sun. In the end, NASA's engineers decided on a tried if not true earthly energy source: nuclear power.

Nuclear power was perfect for space, a giant void free of human life which could play host to a bit of radioactive plutonium 238 dioxide. The plutonium was compact for the amount of energy it gave off - and it lasted a long time. It seemed logical enough. Pop just under 24 kilograms of plutonium in a lead box, let it heat up through its own decay, generate electricity for the probe's instruments, and presto! Galileo would be on its way to investigate Jupiter.

American anti-nuclear activists didn't quite see it that way. They figured what goes up might come down ..NASA assured them Galileo's power pack was quite safe. The agency spent about $50 million on tests which supposedly proved the probe's generators were very safe. They would survive intact in the face of any number of terrible explosions, mishaps and accidents. NASA told journalists that the odds of a plutonium release due to 'inadvertent atmospheric re-entry' were 1 in 2 million. The likelihood of a plutonium radiation leak as a result of a launch disaster was a reassuring 1 in 2700.

NASA's Goddard Space Flight Center, Greenbelt, Maryland

Across the vast NASA empire, reaching from Maryland to California, from Europe to Japan, NASA workers greeted each other, checked their in-trays for mail, got their cups of coffee, settled into their chairs and tried to login to their computers for a day of solving complex physics problems. But many of the computer systems were behaving very strangely.

From the moment staff logged in, it was clear that someone - or something - had taken over. Instead of the usual system's official identification banner, they were startled to find the following message staring them in the face:

      W O R M S    A G A I N S T    N U C L E A R    K I L L E R S
    _______________________________________________________________
    \__  ____________  _____    ________    ____  ____   __  _____/
     \ \ \    /\    / /    / /\ \       | \ \  | |    | | / /    /
      \ \ \  /  \  / /    / /__\ \      | |\ \ | |    | |/ /    /
       \ \ \/ /\ \/ /    / ______ \     | | \ \| |    | |\ \   /
        \_\  /__\  /____/ /______\ \____| |__\ | |____| |_\ \_/
         \___________________________________________________/
          \                                                 /
           \    Your System Has Been Officically WANKed    /
            \_____________________________________________/

     You talk of times of peace for all, and then prepare for war.

This was not going to be a good day for the guys down at the NASA SPAN computer network office.
This was not going to be a good day for John McMahon.